Rotary pump



YAug. 21, 1923.

' 1,465,881 B. THOENS ROTARY PUMP Filed March 50 1922 3 Shutl-Sheet l ulll III IIIIIIIIII|\ ATTORNEYS.

Aug. 21, 1923.n 1,465,881

B. THOENS ROTARY PUM P Filed March 30 1922 3 Shadi-Sheet 3 lvl a IH |||||l il lll l Il III #ses ATTORNEYS.

.radial y Patented Aug. 21, 1923.

UNITED STATES g 1,465,881 PATENT oFFlcs.

BUBCHBD THDENB, 0F NEW YDBK, N. Y,

ROTARY PUIP.

i Application led. larok 80, 1922. Serial lo. 848,057.

To all whom it may concern.'

Be it known that I, BUncHAnD THonNs, a citizen of the United States, and residin at New York city, New York County, ew York State, have invented certain new and useful Improvements in Rotar Pumps, of which the following is a speci cation.

The present invention relates torotary pumps and particularly to rotary air compreesors or exhausters.

The object of the invention is to provide a pum of this class having a number of novel eatures of construction which render it particularly desirable from a practical point of view, the parts beingso desi ned and constructed that a minimum air eakoccurs between the moving parts, a minimum of frictional loss is experienced, while a maximum amount of air can be handled for a pump of a given size. The pump is of the type in w ich a rotary piston, which has a cylindrical core and radially movable piston vane, makes rolling contact with a cylinder which surrounds the same and is eccentric thereto. The surface of the piston core has inlet and outlet ports on-opposite sides of the radially movable vane, and the pump inlet and outlet ports are coaxial with the piston core, the result being that the ra idl rotatin piston throws outward e air w ich enters axially, thus increasing the eflicienc of the pump.

`'Ihe rotatable cylin er is sup Aorted in a novel manner by antifriction ro lers which constrain it to move about a fixed axis parallelto and spaced from the axis of the piston core one of these rollers being yieldingly held against the outer surface of the cy inder by a spring. Means is provided for adjustin the tension of this sprin to cause the ro ler to bear with any desired pressure against the piston core., This yieldmgl held roller bears on the outer surface of t e cylinder opposite the line of contact between the inner surface of the cylinder and the outer surface of the piston core and the tension in the spring determines the deof compression obtained by the pump. m construction and operation of the pump will be disclosed in the following description when taken with the accompanying drawings in which:

Figure 1 is a central transverse section through the pump;

Figure2 is a central longitudinal section;

Figure 3 is an axial section through one end of the piston core;

Figure 4 is an end view, partially broken away, of a modified form of supporting means for the piston core; and

Figure 5 is a side view ofthe same, par` tiarlf broken away.

e pum casing comprises a substantially cylin rical central portion having an integral base 11, and removable end portions or heads 12 and 13 respectively. The

piston core 14 is cylindrical and is supported upon trunnions 15 and 16 which are rotatably mounted in the heads 12` and 13 respectively.` The trunnion 15 is su ported in a rirli 17 held in fixed spaced re ation to the w s of an axial ofset portion 18 of the head 12, by means of spacing ribs 19. The oplposite trunnion 16 is longer and has rigi secured to its outer end a drive shaft 20. oth trunnions 15y and 16 are hollow and are in communication with the interior of the pistoncore 14. The axial aperture 21 in trunnion 15 communicates with a passa e 22 extending substantially radially of the piston core and which in turn communicates with a passage 23 extending longitudinally of the core and having a plurallty of substantially radial outlet ducts 24 leading therefrom, and opening to the outer surface of the core. Inlet ports 25 are spaced adjacent the outlet ports 24` and communicate throu h substantially radial passages, controlled iy spring pressed valves 26 with a longitudinal passage 27 which is connected by the radial conduit 28 to the cylindrical outlet passage 29 in the trunnion 16. A plurality of ports 30 formed in the hollow trunnion 16 bring its interior into communication with the interior of a hollow sleeve 31 which in turn communicates through erts 32 with an annular chamber 33 formed in the tubular extension 34 of the head 13. The chamber 33 has an outlet pipe 34 for conducting away from the pump t e exhaust air or other Huid. The sleeve 31 is non-rotatable and packing material 36 is provided at its ends for preventing leakage of air, a clamping collar 37 and an annular piston-like member 38 being provided to maintain the packing under pressure.

The piston core 14 has transverse annular lian s 39 integral therewith at its ends and is a provided with a substantially radial slot 40 to receive the piston valve 41, which cis-y is normally lpressed outwardly by one or more springs 42. The vane makes air tight joints with the piston core and the end lian es 39 thereof. Normally, the outer end of t e vane engages the inner cylindrical surface of a'rotatable cylinder 43 which makes rolling contact with the piston core and also makes air tight sliding contact with the piston flanges. The cylinder is constrained te move about an axis parallel and spaced from the axis of the piston core by three antifriction rollers 45, 46 and 47 the rollers 45 and 46 being positioned horizontally opposite the axis of the cylinder and the roller 47 vertically above the axis. The rollers 45 and 46 ma be permanently fixed in position. The rolliar 47 is mounted upon an axle 48 which is secured in parallel blocks 49 which are slidablv retained in the hollow upwardly extending portion 50 of the casing 10. A cap 51 closes the top of this upward extension and a spring 52 is positioned in a groove in this cap, the ends of the spring bearing upon blocks 49 and an adjusting screw 53 bearing centrally on the top of the spring. The air inlet pipe is indicated at 54 and it will be seen that the air entering the casing through this pipe passes around the outside of the cylinder 43 before enterin the conduit 21 in trunnion 15, so that this air tends to cool the moving parts of the ump.

Rotation of the shaft 20 in the direction indicated by the arrow in Figure 2 of course effects rotation of the piston and cylinder, the vane 41 moving outwardly and inwardly as the core rotates. As indicated in Figure l, by the arrows, the air issues from ports 24 as the core and cylinder rotate in a clockwise direction, on one side of the vane 4l and passes by the valves 26 and into the channel 27 on the opposite sidel of the piston vane. The degree of compression on the compression side of the vane may be regulated by varying the Ytension in the spring 52. When the pressure on the compression side of the vane rises to a predetermined degree the cylinder 43 will be lifted out of contact with the piston core against the action of spring 52, so that air may escape from the compression to the suction side of the pump between the outer surface of the core and the inner surface of the cylinder.

rlhe air entering axially of the piston is thrown radially therefrom by centrifugal action and the elliciency of the pump, as compared with pumps having radial inlet ports, thereby increased. Friction between the moving parts is reduced to a minimum and hence wear due to the operation. The end flanges 39 being integral with piston core move at the same speed as the cylinder 43 and there is only slight frictional loss due to rubbin of the annular cylinder end surfaces on t e inner walls of the end flanges. The piston vane 41 slides along the inner surface of the cylinder at each revolution a distance only equal to the difference in circumference between the outer surface of the core and the inner surface of the cylinder. The antifriction rollers support the cylinder in a practically frictionle manner on the outside and the upper antifriction roller determines the degrec of pressure with Which the cylinder bears on the rotating core and hence the degree to which the air is compressed.

When the pump is to be used for higher pressures, as in compressing air, the tension of spring 52 is necessarily increased and this causes increased friction between the rotating parts. To avoid such frictional losses the modified structure illustrated in Figures 4 and 5 is resorted to. Here the tension of spring 52 is exerted on the ends of an axle 48 havin spaced rollers 47 thereon bearing against the outer surface of cylinder 43. The set screw 53' which regulates the tension of spring 52 has threaded engagement with one member of a frame which also rotatably supports axles 60, 61 and 62, and which is supported Within the casing (indicated in dotted lines in Figure 4). l Rollers 45 and 46 are mounted on axles 6() and 61 respec tively and these rollers bear against opposite sides of the cylinder 43 to prevent horizontal movement thereof. Spaced rollers 63 and 64 are mounted on the axle 62 and these rollers bear against the flanges 39 of the piston core to support the same. The piston core is thus supported by these rollers and not b the inlet and outlet tubes 15 and 16 and t e core will rotate with little friction Whatever the tension of spring 52 may be.

One skilled in the art will appreciate the advantages of the invention and will realize that it may be varied considerably in other ways without departing from its spirit and sco e.

aving thus described my invention what I claim as new and desire to secure by Letters Patent is 1. A rotarypump including in combination, a rotatable piston having a cylindrical core. annular transverse flanges rigid with the core and a vane movable radially relatively to the core and making air tight joints with the core and end flan es, and a rotatable core making air tight joints with the piston vane, the piston core, and piston end flanges.

2. A rotary pump including in combination, a rotatable piston having a cylindrical core, annular transverse end dan s rigid with the core and a vane mova le radially relatively to the core and making air tight joints with the core and end flanges, a rotatable cylinder making air 3, A rotary pump including in combination, a rotatable piston having a cylindrin rigid with the core,

core,

let ports in its cylindrical surface,

cal core, annular transverse end flan rigid with the core and a vane mova le radially relatively to the core and making air tight joints with the core and end flanges, a rotatable cylinder making air tight joints with the piston vane, the piston core, the piston end anges, and means yieldingly holding said cylinder against said core including a spring, and a device for adjusting the tension of said spring.

f4. A rotary pum including in combination, a rotatable piston having a cylindrical core, annular transverse end flan es rigid with the core and a vane mova le radially relatively to the core and making air tight joints with the core and en flanges, a rotatable cylinder making air tight joints with the vane, the piston core the piston en flanges, and means yieldingly holding said cylinder against said core including a roller mounted to rotate about an axis parallel to the axis of said core, and a spring which forces said roller against the outer surface of said cylinder.

5. A rotary ump including in combination, a rotatab e piston having a cylindrical core, annular transverse end dan s and a 'vane mova le radially relatively to the core and makin air `tight joints with the core and en` llanges, .a rotatable cylinder making air tight joints with the piston vane, piston and piston end flan three sp rollers bearing against t e outer surface of said cylinder to confin its movement to rotation about a xed axis, and rmeans for yieldingly hold' one of said rollers against said cylin er.

6., A rotary um including in combination, a rotatab e iston having a cylindrical coreA supporte at its ends upon hollow trunnions and having spaced inlet ang outt e inresilient means, and' en let ports being in communication with one of said trunnion passa and the outlet being in communication with the other ot said trunnion passages, annular transverse end {ianges for the core, radially relative to the core and making air tight joints with the core and end flanges, and a rotatable cylinder for making air tight joints with the piston wane, piston core' and piston en d flanges.

7. A rotary air ump including in combination, a rotata le piston comprising a cylindrical core having a substantially radial outlet air passage and an axial air inlet opening communicating therewith whereby rotation of said iston will throw outwardly from said out et rts the air which enters axially to said in et port.

8'. A rotary air pump including in combination, a rotatable piston cal core, coaxial trunnions on which core is mounted,v said trunnions bein hollow and the opening through one o said trunnions constituting an inlet port while the opening through the other trunnion constitutes the outlet port.

9. A rotary pump including in combisaid nation, a rotatable piston having 'a cylindri' cal core, a cylinder surroundin said core, resilient means pressing sai 'cylinder against said core and anti-friction means on the opposite sideof said core from the resilient means and engaging and supporting the core. v

10. A rota pump including in combination, a rotata le piston, having a cylindrical core and annular end flanges secured thereto, a cylinder surroundingu said core, resilientl means pressing said cylinder against said core :and anti-friction means on the opposite side ging the peripheranges, for supporties of said annular in 'the core.

testimony whereof I hereunto my signature. l

mmcimnA 'rit-rosas. v

having a cylindriand a vane movable 'lol of said core from the 

